1. Field of the Invention
The present invention relates to an image forming apparatus and an image forming system, particularly to an image forming apparatus and an image forming system for being able to utilize an application in which a Web browser is used.
2. Description of the Related Art
There is known an image forming system including an image forming apparatus (such as an MFP (Multi-Function Peripheral) including a scanner function, a facsimile function, a printer function, a data communication function, and a server function, a facsimile machine, a copying machine, and a printer, and the like) and a Web server that provides a Web application. In the image forming system, the Web application provided by the Web server can be utilized using the image forming apparatus by accessing the Web server from the image forming apparatus.
In some image forming apparatuses of the image forming system, the Web application that is frequently utilized in utilized Web applications can be registered in the image forming apparatus. In the image forming apparatus, the Web application can easily be utilized by registering the Web application. The Web application and cache information on the Web application are stored in the image forming apparatus, which allows the Web application to be quickly utilized. Additionally, a traffic of a network constituting the image forming system can be reduced in utilizing the Web application.
During the use of the Web application, the image forming apparatus acquires data utilized when using the Web application (for example, document data or image data of a Web page) from the Web server similarly to a usual browse of the Web page. At this point, the acquired data is stored as the cache information in the image forming apparatus. Since then, in the case that the image forming apparatus accesses the same Web page, the cache information is utilized when the stored cache information can be utilized, the Web page relating to the Web application is displayed to enable the Web application to be utilized.
Japanese Patent Laying-Open No. 2009-110216 discloses a server-based computing system, in which an important degree of a frequently-browsed URL is assigned to give a priority in each Web page and the cache information on the Web page having the low priority is deleted when a domain of a cache memory needs to be ensured.
Japanese Patent Laying-Open No. 2009-070373 discloses a communication apparatus, in which application software is received and executed for the purpose of trial use and information on the application software, which is stored in a nonvolatile memory, is deleted after Web browser software is executed.
Japanese Patent Laying-Open No. H11-316727 discloses a security system in which data of a security target is deleted from a disk cache when a WWW browser software is ended.
Conventionally, unless the cache information on the Web application is deleted in accordance with a manual manipulation of a user, the cache information is retained in the image forming apparatus for an indefinite time or a predetermined time. Therefore, in the image forming apparatus in which the Web application can be registered, the cache information remains retained even if the registration of the Web application retained in the image forming apparatus is cancelled.
When the unnecessary cache information remains retained, a free space is reduced in a storage (such as an HDD (Hard Disk Drive) and a memory) of the image forming apparatus. For example, it is necessary to use the storage having a large capacity in order to store necessary information as much as possible. However, the use of the storage having the large capacity increases production cost of the image forming apparatus. The capacity of the storage can be ensured when the unnecessary cache information is intentionally deleted. However, necessity of an explicit deletion manipulation increases a manipulation burden of the user. The capacity of the storage can be ensured when the cache information is deleted in a short time irrespective of the cache information. However, in this case, it is necessary to acquire the cache information from the Web server again when the Web application that remains registered is utilized next time. Therefore, convenience is degraded during the use of the Web application.
Japanese Patent Laying-Open Nos. 2009-110216, 2009-070373, and H11-316727 disclose no effective countermeasure against the problem of the cache information associated with the cancel of the registration of the Web application.